Efficacy and Safety of Recombinant Human Prourokinase in the Treatment of Acute Ischemic Stroke Within 4.5 Hours of Stroke Onset: A Phase 3 Randomized Clinical Trial

IMPORTANCE: Recombinant human prourokinase (rhPro-UK) is a thrombolytic agent that has shown promising findings in a phase 2 clinical trial in patients with acute ischemic stroke (AIS). OBJECTIVE: To evaluate the efficacy and safety of rhPro-UK thrombolysis within 4.5 hours of symptom onset in patients with AIS. DESIGN, SETTING, AND PARTICIPANTS: This randomized, alteplase-controlled, open-label, phase 3 clinical trial was conducted from May 2018 to May 2020 at 35 medical centers in China. A total of 684 patients were screened and 674 patients were enrolled. Included patients were aged 18 to 80 years with a diagnosis of AIS and received treatment within 4.5 hours of stroke onset. Data were analyzed from June to October 2020. INTERVENTIONS: Eligible patients were randomly assigned (1:1) to receive intravenous rhPro-UK or alteplase. MAIN OUTCOMES AND MEASURES: The primary objective was to assess whether rhPro-UK was noninferior to alteplase. The noninferiority margin was a between-group difference of less than 10%. The primary outcome was a modified Rankin Scale score of 0 to 1 at 90 days. RESULTS: Among 663 patients in the modified intention-to-treat population (mean [SD] age, 61.00 [10.20] years; 161 females [24.3%]), there were 330 patients in the rhPro-UK group and 333 patients in the alteplase group. The median (IQR) baseline National Institutes of Health Stroke Scale score was 6.00 (5.00-9.00). There were 23 deaths, and 619 patients (93.4%) completed the 3-month follow-up. The primary outcome occurred in 215 patients (65.2%) in the rhPro-UK group and 214 patients (64.3%) in the alteplase group (risk difference, 0.89; 95.4% CI, −6.52 to 8.29). Symptomatic intracerebral hemorrhage occurred in 5 patients (1.5%) in the rhPro-UK group and 6 patients (1.8%) in the alteplase group (P > .99). Systemic bleeding within 90 days occurred more frequently in the alteplase group (141 patients [42.2%]) than the rhPro-UK group (85 patients [25.8%]) (P < .001). By 90 days, 5 thrombolysis-related deaths each had occurred in the rhPro-UK group (1.5%) and alteplase group (1.5%) (P > .99). CONCLUSIONS AND RELEVANCE: This study found that intravenous rhPro-UK within 4.5 hours of AIS onset was noninferior to alteplase. The rhPro-UK group showed a similar rate of symptomatic ICH but fewer cases of systemic bleeding than the alteplase group. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03541668